US news network ABC has suspended its chief investigative reporter after he made a "serious error" about Donald Trump's former top aide, Michael Flynn.

Brian Ross reported Mr Trump was a candidate when he directed Michael Flynn to make contact with Moscow.

But he later clarified that the orders came when Mr Trump was president-elect.

The actions of Mr Trump's campaign team are under investigation over whether they colluded with Russia to help sway the election in his favour.

On Friday, Michael Flynn - who Mr Trump sacked as national security adviser - pleaded guilty to lying to the FBI about his contacts with Russian officials prior to the president's inauguration in January.

As part of a plea bargain, Mr Flynn agreed to co-operate with special prosecutor Robert Mueller's investigation into possible collusion between the Trump campaign and Russia ahead of the 2016 election.

US intelligence agencies have already concluded that Russian President Vladimir Putin directed a state effort to influence the US election in favour of Mr Trump.

What did the original report say?

Brian Ross's special report was aired after Mr Flynn's plea deal was announced on Friday.

Quoting a single anonymous source, it said he was prepared to testify that Mr Trump had directed him to make contact with Russian officials when he was still a candidate for the presidency.

If found true, the claim would have conflicted with the president's comments at the time of Mr Flynn's sacking earlier this year. In February, he told reporters: "No, I didn't direct him, but I would have directed him if he didn't do it, okay?"

Off the back of the report, Wall Street's main indexes fell by more than one percent.

Why was a correction issued?

In a later edition of ABC's World News Tonight, Mr Ross clarified that his source had in fact said that Donald Trump's orders came during the presidential transition, after the election had taken place.

"It was shortly after the election that President-elect Trump directed Flynn to contact Russian officials on topics that included working jointly against ISIS (so-called Islamic State)," he said.

But the news network was criticised for simply clarifying the error and was later forced to issue a full correction.

Mr Ross, 69, also took to Twitter to comment on the mistake, saying: "My job is to hold people accountable and that's why I agree with being held accountable myself."

The journalist has been criticised in the past for previous errors, including suggesting that the gunman in a mass shooting at a cinema in Colorado had a connection to the conservative Tea Party group.